Device for operating trap-doors



(No Model J. C. FRENCH.

DEVICE FOR OPERATING TRAP DOORS.

' No. 394,259. Patented Dec. 11, 1888.

Winesaes;

N, PEYERS Phvlu-blhognphar, Washington, DJ;

UNITED STAT- s PATENT OFFICE.

JAMES C. FRENCH, OF BROOKLYN, NE\Y YORK.

DEVICE FOR OPERATING TRAP-DOORS.

SPECIFICATION forming part of Letters Patent No. 394,259, dated December11, 1888.

Application filed May 16, 1888- Serial No. 274,105. (No model.)

To all whom, it may concern:

Be it known that 1, JAMES C. FRENCH, of Brooklyn, in the county of Kingsand State of New York, have invented a new and useful Improvement inDevices for Operating Trap- Doors, of which the following is aspecification.

This invention relates to endless screws applied to trap-door frames ingear with curved toothed racks attached to the doors.

I will proceed to describe such a trap-dooroperating device embodyin myimprovement, and afterward point out the novelty in claims.

In the accompanying drawings, Figure 1 represents a vertical section ofa trap-door, a part of the frame thereof, and shows applied thereto adevice embodying my invention. Fig. 2 is a sectional view, taken atright angles to Fig. 1, of a part of the trap-door frame and of thedevice for operating the door. Fig. 3 is a plan view of the device whichconstitutes the principal feature of my invention, and Fig. 4 is aperspective view of the rod for turning the endless screw.

Similar letters of reference designate corresponding parts in all thefigures.

A designates the trap-door frame; B, the trap-door; (l, the toothed rackattached to the trap-door, and D the endless screw, gearing with thesaid rack, for opening and closing the door.

E designates the hanger in which the endless screw D is supported. Thishanger consists of an open frame closed at the bottom but open at thetop and furnished on opposite sides with two lugs, 6, through which itis bolted to the trap-door frame A by bolts a. In the bottom of thishanger is the bearing for the lower journal, (I, of the endless screw D,the upper journal, d, of which has its hearing in a removable cap-plate,D, which is fitted into a seat in the open top of the hanger. This seatis shown at l) in Fig. 1 as tapered vertically, and is shown at c c inFig. as having recesses in its sides to receive projections (2, providedon the sides of the hanger, the said projections and recesses serving tokeep the said cap-plate from passing out laterally from the hanger,while the taper sides 19 b of the seat serve to support the said platevertically.

Then the cap-plate D is in the seat in the hanger, its upper surface isflush with the top of the hanger, and when the hanger is bolted into itsplace by the bolts A the cap-plate D is thereby secured in place withoutfurther.

fastening. The cap-plate is, as shown in Figs. 2 and 3, wider than thehanger, so that the portion (7 which contains a slot, (.7 which receivesthe rack and confines it to the endless screw, projects beyond the inneredge, a, (see Fig. 2,) of the frame A.

The removaljfle cap-plate provides for the convenient insertion of anendless screw hav ing its journals integral with it, the cap-platebeingremoved to drop the screw into the yoke from above and beingafterward replaced to receive the upper journal of the screw and confinethe screw in an upward direction.

The lower journal, (I, of the endless screw projects down some distancethrough the hanger, and has provided near its lower end two lugs, f, onopposite sides, for the reception of the bifurcated hook g,'provided onthe upper end of the rod F, Figs. 1 and 4, the lower end of which isfurnished with a crank, 72. This rod, which may he laid aside when notrequired for use, may be of any length, so that by it a man standing onthe bottom of a deep cellar or vault may reach the screw for the purposeof turning it to operate the trapdoor at the mouth of said cellar orvault.

In order to provide for the insertion of the lower journal, which isprovided with lugs, through the bottom of the hanger E, the journal-bearing in the bottom of said hanger is provided with a notch oneach side, as indicated at d in dotted lines in Fig. 1.

hat I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination, with a trap-door frame and an endless screw appliedthereto for 0peratin g a rack on the trap-door, of the hanger having anopen top and laterally-projecting lugs and containing the bearing forthe lower journal of said screw, and a removable flush cap-platecontaining the bearing for the upper journal of the screw and fitting toa seat in the open top of the hanger, substantially as described,whereby the bolting of the hanger to the under side of the frame is madeto secure the cap-plate in the hanger and hold the 3. The combination,with the hanger E and an endless screw, D, having its lower journal, (1,extending through said hanger and pro- I 5 vided with lugs f on oppositesides, of the rod F, having a bifurcated hook on its upper end and acrank on its lower end, substantially as and for the purpose hereindescribed.

JAMES C. FRENCH.

lVitnesses:

FREDK. HAYNES, Jos. W. Ron.

